1. Field of the Invention
The present invention relates to strain relief clamps for cables.
2. Related Art
In many applications of electric cables in such environments as aircraft, spacecraft, and the like, the cables are often subjected to flexing and pulling in various directions due to the movement of the craft itself. In applications where cables on one side of a wall are connected to cables on the opposite side of the wall, a connector assembly is used. The connector assembly normally contains a multiplicity of end pins for plugging or inserting into a wall-mounted receptacle to effect an electrical connection. However, because of the stresses on the electrical cable, it is difficult for the connector assembly to maintain a stable connection without a strain relief clamp.
Various types of strain relief clamps are in existence today. Some devices use a cable or wire bundle guide arm such as the wire bundle guide arm described by McKnight in U.S. Pat. No. 3,732,527. Some strain relief clamps such as those called saddle clamp type strain relief clamps use an assembly of screws, nuts and lock washers to accomplish clamping of the cable wherein the assembly of parts are generally exposed. These exposed parts create a potential for damage due to exposed sharp edges to both personnel and equipment, and such elements could be lost during assembly or maintenance, possibly resulting in foreign object damage to the aircraft or other equipment.
In the saddle clamp type of strain relief clamp, the saddles are generally screwed together at their respective ends, resulting in a relatively high stress at the center of each saddle and compound stresses at the threaded screw hole ends. These compound stresses tend to bend the saddles and cause stress fractures and eventually failure of the entire clamp, which may then affect the overall operation of the aircraft or other vehicle. The present invention eliminates the need for such exposed parts.
There is a need for a reliable cable clamp which is more stable than prior cable clamps, and which is self actuating by turning a housing body. There is also a need for a cable clamp having internal clamp means which is protected from external impact and which will not loosen through normal vibration. The present invention provides a cable clamp meeting these needs.